![Phase-dependent (colors) apparent albedo spectra from our updated rfast model for an ocean-covered Earth and assuming 75% cloud coverage (left). The equivalent figure adapted from the high-fidelity Earth simulation data of Ryan & Robinson (2022) are shown for comparison (right). All spectra are at a resolving power (λ/∆λ) of 140. Deeper water bands in the rfast simulations are due to this model only including lower-atmospheric clouds, whereas the Ryan & Robinson (2022) simulations include high-altitude clouds that have lower contrast in gas absorption bands (as they obscure the deep atmosphere). -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/Retrieving.png?resize=1200%2C717&ssl=1)
[astro-ph.EP] Future space telescopes searching for extraterrestrial life require methods to detect environments that can potentially support life.
biosignature
Posted inBiosignatures & Paleobiology
Compositional Heterogeneity Structures Microbial Microhabitats across Distinct Mineral Substrates
[biorxiv.org] Microbial communities living on and in rocks operate at the microscale, where interactions with minerals fundamentally shape community structure and function. Yet the relationship between micron scale mineralogical configurations […]
Posted inBiosignatures & Paleobiology
Determining The “Biosignature Threshold” For Life Detection On Biotic, Abiotic, or Prebiotic Worlds.
[Astrobiology (Journal) via PubMed] The field of prebiotic chemistry has demonstrated that complex organic chemical systems that exhibit various life-like properties can be produced abiotically in the laboratory.
![Waste-heat temperature–luminosity phase space. Existing midinfrared searches occupy the warm band (orange); cold computational radiators fall in the far-infrared/submillimetre band (green) towards the CMB floor. Grey lines show 345-GHz flux-density contours for a source at 100 pc, from equation (10), which is linear in the fractional waste-heat luminosity 𝑓 on the vertical axis; the figure thus covers partial swarms and complete spheres (𝑓 = 1) alike. Markers indicate a complete 1 L⊙ cold sphere, the level of the archival debris-survey limits (Section 6.1), and the domain of warm mid-infrared searches. -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/Slysh.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Slysh Haloes: The Waste Heat Of Cold Computing As A Submillimetre Technosignature
[astro-ph.IM] Searches for Dysonian waste heat have operated almost exclusively in the mid-infrared and are therefore sensitive primarily to technology radiating at 100-600K. We argue that mature, computation-dominated civilisations may […]
Posted inExtremeophiles and Extreme Environments
Cultivation Of Halophilic Archaea In Shallow Subsurface Martian Conditions Has Implications For Extant Life On Mars
[biorxiv.org] The present-day martian surface is generally considered inhospitable to life because of low atmospheric pressure, intense surface radiation, global desiccation, and oxidizing chemistry which has been increasing since the […]
Posted inBiosignatures & Paleobiology
Opportunity to Contribute to NASA DARES Community White Paper on Phototrophic Biosignatures
[Prebiotic Chemistry and Early Earth Environments RCN] Opportunity to contribute to the “White Paper on Phototrophic Biosignatures: Research Priorities for the Search for Life on Other Worlds“, developed as community […]
![Earth biosignatures through time and their reflected light spectra. The left subplot shows estimates of Earth’s bulk atmospheric composition through time (advancing from top to bottom), and the figures on the right show the corresponding reflected light spectra considered in this study. Key absorption features for biosignature gases (O3, O2, CH4) and suggested long- and short-wavelength cutoffs are highlighted (as discussed further in Sections 3 and 4). Adapted from National Academies of Sciences, Engineering, and Medicine (2021) and LUVOIR and HabEx Final Reports (LUVOIR Team, 2019; Gaudi et al., 2020). -- [Astrobiology (Journal)]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Wavelength.png?resize=1200%2C719&ssl=1)
Posted inBiosignatures & Paleobiology
Wavelength Requirements for Life Detection via Reflected Light Spectroscopy of Rocky Exoplanets
[Astrobiology (Journal)] Searching for signs of life is a primary goal of the Habitable Worlds Observatory (HWO). However, merely detecting oxygen, methane, or other widely discussed biosignatures is insufficient evidence […]
Posted inBiosignatures & Paleobiology
Orbital Biosignature Assays: FLEX Photosynthesis Satellite Fueled
[ESA] Europe’s newest eye on the health of Earth’s vegetation has taken another crucial step towards orbit – the European Space Agency’s FLEX satellite has been fueled at Europe’s Spaceport […]
Posted inBiosignatures & Paleobiology
The Effects of M Star Age Dependent Ultraviolet Emission on Detecting and Interpreting Exoplanet Biosignatures
[astro-ph.EP] Given their abundance and observational advantages, M stars will arguably be the best candidates for characterizing and searching for biosignatures on terrestrial exoplanets in the near future.
Posted inBiosignatures & Paleobiology
Direct Dating Of 3.5 Ga Biogenic Carbon In A Microbial Mat Remnant, Singhbhum Craton, India
[PNAS]. Kerogen, insoluble organic matter preserved in sediments, represents some of the earliest known terrestrial biosignatures which have provided important insights into the origin of life and planetary habitability.